One waiting secretly, putting last of stock in drawer? (6)
I believe the answer is:
lurker
'one waiting secretly' is the definition.
(someone who lurks)
'last of stock in drawer?' is the wordplay.
'last of' indicates one should take the final letters.
'in' indicates putting letters inside.
'drawer?' becomes 'lurer' (I can't explain this - if you can you should give a lot more credence to this answer).
The last letter of 'stock' is 'k'.
'k' placed within 'lurer' is 'LURKER'.
'putting' acts as a link.
(Other definitions for lurker that I've seen before include "One remaining hidden" , "Someone lying in wait" , "One waiting in ambush" , "One lying in ambush" , "One lying hidden" .)